The proposed research utilizes the occurrence of a family crisis, diagnosis of a mother's breast cancer (BC), as a naturalistic experiment to evaluate the impact of stressful life events or conditions on the adjustment and well-being of children. BC is selected for study because it is one of the most common forms of cancer and causes of death among women in their child rearing years. Additionally, unlike many other stressful events occurring in the life of a child, the diagnosis of maternal BC is not associated with antecedent psychosocial characteristics of the child, mother, or family. Previous research has suggested that parental physical illness challenges the entire family and may increase the risk of children to experience emotional, social, and behavioral difficulties. Unfortunately, published work in this area is limited by research designs that fail to include appropriate comparison samples and do not obtain relevant data from sources outside the family. Women recently diagnosed with BC who have school-aged children (8-15 years) will be recruited for participation. For each target child whose mother has BC, a same race, same gender, and similar-aged matched classroom comparison peer (MCCP) whose mother does not have cancer will be recruited as a case-control. Identical data will be obtained from multiple sources in children's classrooms (teachers and peers) and families' homes (mother, father, and child) to allow tests of group differences social functioning and emotional well-being. Specific Aim number 1. Compare the social functioning of children whose mothers have been diagnosed with BC to MCCPs. Specific Aim number 2. Compare the emotional well- being of children whose mothers have been diagnosed with BC and MCCPs. Specific Aim number 3. Evaluate whether difficulties in social functioning and emotional well-being evidenced by children of women with BC are mediated by family context variables. Specific Aim number 4. Utilize a case controlled design to evaluate whether the impact of maternal BC on children's social functioning and emotional well-being is moderated by child demographic and disease specific variables. Specific Aim number 5. Collect data regarding family communication about the BC diagnois, treatment, and prognosis in terms of parental beliefs about the value of such information to children and their actual attempts to discuss these factors within the family. Examine associations of cancer-specific communication with broader family context and child outcome variables.